The objective of this proposal is to develop multi-lumen steerable needles capable of controllable curved paths through both soft tissues and open or liquid-filled cavities. The pre-curved lumens, or tubes, are nested within each other in a telescoping fashion, enabling control of the needle's shaft shape and curvature in open cavities. Our needles will also harness tip forces for steering, dynamically modifying their forward cutting trajectory through soft tissues. The broad, long-term objective of this work is to create a needle that is (1) more accurate than existing needles, and (2) more dexterous than existing needles. Accuracy is essential, because efficacy in nearly all needle-based interventions (biopsy, therapy delivery, etc.) is strongly correlated to the accuracy with which the needle tip is placed at the desired target. Enhanced dexterity allows the needle to reach previously inaccessible locations, which will enable entirely new minimally invasive percutaneous treatments. Specifically we foresee compelling applications in lung cancer treatment, deep brain stimulation, and prostate brachytherapy - areas where there are anatomical obstacles that require the needle to maneuver through curved trajectories. This research directly aligns with NIH's mission to improve public health;our new multi-lumen steerable needles will enable minimally invasive, percutaneous access to previously unreachable clinical targets for biopsy, local drug injection, radiation dose delivery, surgical interventions, and other procedures. The specific aims of this research are to (1) Design and model multi-lumen steerable needles, (2) Develop simulation and planning software, (3) Construct an integrated pre-clinical testbed capable of robotically control- ling multi-lumen steerable needles. The methods used to achieve these aims will include kinematic and beam mechanics models for the tip and shaft trajectories of flexible needles in soft tissues, optimization-based motion planning techniques, and finite element simulation. We will evaluate the new devices and methods we develop in phantom and ex vivo tissues to establish the feasibility of the approach. Working with clinical collaborators in urology and cardiothoracic surgery we will develop a system that accounts for relevant clinical constraints and objectives, paving the way for future animal, cadaver, and human studies. In summary, we propose a multidisciplinary effort combining mechanical engineering, computer science, and biomechanical modeling to design and develop hardware and software that will dramatically increase minimally invasive access to many sites of clinical importance within the human body. PUBLIC HEALTH RELEVANCE: We will develop multi-lumen steerable needles capable of controllable curved trajectories in the human body. These needles will enhance needle tip placement accuracy under image guidance, thereby increasing the efficacy of a wide variety of needle-based interventions. They will also enable entirely new percutaneous procedures by endowing surgical tools with the ability to maneuver around obstacles to reach previously inaccessible clinical targets.